Auxiliary powered vehicle construction



pril 29, 1947.

' AUXILIARY POWERED VEHICLE CONSTRUCTION 3 sheet-sheet i Original Filed Deo. 19, 1938 April 29, 1947. G. D. wlLcox 2,419,929

AUXILIARY POWERED vEHIcLE'coNsTRUcTIoN original Filed Dec. 19, 195s 5 sneis-sheet 2 INVENTOR. 'fafff h// an ATTQRNEY.

pril 29, 1947. G. D, WILCQX 2,419,929

AUXILIARY POWERED VEHICL CONSTRUCTION Original Filed Dec. 19, 1938 3 Sheets-Sheet 3 ATTORNEY.V l

Patented Apr. 29, 1947 STATES PATENT orties AUXHIARYPOWEREDEHIGLE; GONSTRUCT-IDN.Y

George D: Wilcox; Detroit, Mich., assignorlofione' half to Frederick J. Haynes, Detroit; Mich.;- Frank- C. Cook; executor Frederick.. Jl' Haynes, deceased; John Conway;(loolrxecliteitU vtGemfsefD; Wilcox deceased Qrignal application. December 19;` 1938;- Serial* Divided and-1` ths application October 11, 1939;-Se1ia1No. 298,913

19 Claims-l 'I fhitnventien'. relates tofI vehicles, and Y more.V partilllarly isa directed casanj improved power,A

drive, combination for heavy;duty`,vehicles .such as rtrucks, busses, rail f cars-*zand "the like.v

TIES-.application is atdirision, of,.my copending application;K Serial 'No.: 246565 ledyDecember Present daml transportation requirements are such; that trucks and'similar to?carryspredeterminedpay loads at `fairly consistent .speeds "over:r flat country. However,l it@ is commonI experienceV that. suchA vehicles are4 freq-uentltn:overloaded,l and; even. whennot. overloadedxthe powerinV such: trucks is notk sucient to maintainadequate speed, of lthe vehiclein climbing` grades. and Ythe `liketin hilly or mountamous country. Such1.vehicles crawl i-upmgrades: under load at speeds which are` so slow-c astocauser numerous accidents duey to attempts y of trailing-f, higherspeed. -zvehicles .-to :pass the slow moving truck. or bustwhenigoingrup hill; This.r occursinspitevofhighway regulations prohibiting i passing ,under l such conditions, due f mainly to v the. extremelyl slow. speed =of theheavily loaded-- vehicle yandthe'-irnpatience ofthe trailing fdriver.

In... .attempting tofovercome--such a situation 'it f hasbeeornel increasinglyl apparent that'the solu- -V tion Vdoes not lie in 4tryingto .prevent passing under such sconditions-4 but 'rather'` in speeding up i 4the slow vehicleto a-point wherefit will not unduly. retardltraliic-on grades;- Speedsoftwenty to thirty-ve--mileseper hourg vfor example, would do much: to .l eliminate theV Y accidents as `at suchv speeds trafc Ywouldnoti be impededto anextent@ suchasto cause disregardl for the obvious-dangersl` inherent lin `passing under such conditions.

Onetmanner -newhichuthe Ispeed fof'A the .transl portsvehiclecould be increased in climbing grades. Wouldfhes-toinstallularger. and.` more powerful engines therein,-adequate :to maintain the desiredf Vehicles Varepowered i lllv speeds V-on grades., However, this .is :impractical since itL would produce uneconomical operation o the :power :unit under normal drivingfconditions on atater-rain;:and the, available power would be r being- Wasted; during;

utilized; only,Y occasionallyt the time that vfull'fpower was. not-required.r

I f'have; conceived. cria manner of solving this problem which'will resulto-in economicaloperation of .thetruckorbus-at all;times,without requiring Y the use of an extremely powerful engine Whichiis. utilized at "full-.capacity only ,at infrequent inter valsa@ The primary concept'Of-my nventionfs the provision lof; fan-auxiliary ornboosterpowerunit, of; atl-.sizeifandecapaeitywsuchrasato furnish,with:theVv standar-:dpr:primary-reweraunit l now-:installed vin ,ativeat-,below 50 %-1full-openfthrottlerfV Y 2'.: ther'vehiolegq-amplepowerformaintaining the-idee. siredespeed ongrades; Ilout which is only in operV-f ation;` Whenfsuch power is required, and fatother.: times is inoperative. This-eliminates;thefunecoen nomical constant operation of aflargevpowerz-unit at alltimes,fwhetherfulll powenis requiredon not.

@ne of, the-primaryV objects of@ the-,presentav invention is to provide agsecortldary--,l onlooosterA powergunitrdrectly coupled tothe-power trainsfof the vehicle.

Another Vobject of :the present invention-desto interconnect the looostervpowerunit @andA apowerf input gear disposedin.; driving; relationfntoffthe clutchs; shaft,- of a` variable; speed transmissiorcf` vthatzisAA operatedqfbyfthe mainrpwer unit offthet comese-up; immediately to full: torque, and"r addsav its drivi'ngzpelort -to fthat ofv the4 primarie power-- sourceto deliver sufficienttorque for maintainingf; a predetermined gspeed: Shouldrthespeed rconer tinue to decrease, even with both units operating@ due to extremely-:heavyfloadslor. ,extremely steep the systemcan`- befgarrangedeto-aallowii grades; shiftingirinto.the'f'nextzzgear: ratio, and-but w; engines icanifbeeusedrforfpowerfin'such-'gearn'ati Obviouslyyfit-fwould -not loe-desirable to :operates thepboosteri engine-when moving; awayffroIn-a-L':

s top on level territory in low gear with standard;

axle constructions,- and consequently a. control may he., provided toLinsui-e thatftheloooster:engine'e will; operate 1 in fhighgr orfintermediate f :gears sin speedangesybetween sayl and 35'mi1eslper hourlf.

Ot 'fcoursefwithgmodiiied -drivinggear assemblies it is' contemplated fthatrv loe. used at algltimes the booster engine :may/: L

matiaaor a-combination of -lcotl1.-l I-have found that; the,;control responsive-fte .throttle positionr mayl readilyfloe a vacuum-control v-frorn vthe sintaker manifold setfztoxoperate"between 90% -to '-10v,0-%y inoperae When@w additional; powerfis ,i required` Control may; be electrical` "orvpneu-L:

The speed control, that is, responsive to speed of the vehicle, may be electrical, controlled from a motor-driven generator, cut in and cutout at certain speeds, or responsive to certain propeller shaft speeds, or may be a mechanical control of the centrifugal or governor type.

The two controls must necessarily be interlocked in such manner that neither will independently cause the booster engine to operate.

Another feature of the present invention resides in the provision of a simplified booster mechanism construction which may be manufactured.

and sold as a unit for attachment to vehicles now in use, without requiring any appreciable modification in the drive mechanism already installed in the vehicle. Y

Other objects and advantages of the present invention will appear more fully from the following detailed description which, taken in con- ;lunctionwth the accompanying drawings, will disclose to those skilled in the art the particular construction and operation of a preferred form ofthe present invention.

In the drawings:

Figure 1 is a side elevational view, shown somewhat diagrammatically, embodying the invention;

Figure 2 is a top plan View of the vehicle chassis shown in Figure 1; and

'Figure 3 is a diagrammatic showing of one form of control for the system.

Considering now the drawings in detail, a truck chassis is indicated generally at I and includes a `front axle assembly I2 having the steering Wheels I3 secured at opposite ends thereof. The chassis is also provided with a rear axle I4 which may be of the banjo full-floating type, andA may have either single or dual wheels I5 j'ournalled at the outer ends thereof At the center of the rear axle .there is provided a differential I6 of any standard orconventional construction to which is connected the propeller shaft or torque tube I1 inclined-slightly upwardly and extending toward the power plant at the forward portion of the vehicle.

The chassis I0, which-comprises the two side rails I8 land suitable cross members, some of which are not shown, member I9, is adapted to support an operators cab 2D, shown more or less in silhouette in Figure 1, and of course a truck body of any desired type is mounted on the chassis rearwardly of the cab 20.

It is to be understood that the' present invenparts being of a vehicle tion is equally well applicable to a tractor trailer combination or to a conventional type of truck structure, and if the former type of construction is employed, the chassis I0 will support a suitable fth wheel mechanism for coupling the trailer thereto.

-The main or primary cle includes a primary engine 22, which may be an internal combustion engine, or may be of the Diesel type if desired, Aand which is supported in more or less conventional manner between the side railsV I8 adjacent the forward end of the vehicle and extends Vpartially over the front end of the vehicle 'It isto be understood that the present invention is not limited to any specic location of the engine 22, and the illustrated showing thereof is intended'for descriptive purposes only and in no way is to be construed as limiting. This engine is provided with the usual type of cooling system, including the radiator with relays wound to.

including a center cross` power plant of the vehie tor, and a water pump operation or automatically,

4 23 disposed forwardly thereof and suitably con-f nected to the cylinder head of the engine and to the cylinder block in the conventional manner. A suitable fan or otherimechanism may be employed for drawing air through the radiais also preferably provided for circulating the cooling fluid. The particular type and arrangement of these parts forms no part of the present invention except to show the general relationship and to indicate that the en gine 22 may be of any conventional type such as provided by the truck manufacturer.

. Secured to the flywheel housing of the engine 22 is a suitable clutch housing 24 enclosing a conventional type of clutch mechanism, which is adapted to be controlled through suitable pedal as desired. To the the clutch housing 24 there is secured a transmission case 25 containing any type of suitable truck transmission, such as is normally provided with such vehicles, including a clutch shaft 24 (Figure 1) into the rear end of which propeller shaft I1 is journalled. This transmission has a pedestal portion 26 through which the gear shifting lever 21 extends, the lever 21 being adapted for shifting the gears in the transmission through the various speed ratios.v

VThe transmission is adapted to be provided with a countershaft 28, which is shown in dotted lines in Figures 1 and 2, that carries a gear 28 driven by a driving gear 25 on the clutch shaft 24'. The countershaft 28` departs from the conventional style in that at one end thereof there is provided a gear 29' keyed to the shaft and intermeshing with a gear 30 enclosed within a suitable laterally extending housing 32 which is bolted or otherwise secured to the side of the transmission case.

Within the housing 32 there is provided a third gear 33 having constant meshing engagement with the gear 33, and therefore adapted to rotate with the rotation of the countershaft 28. From the laterally extending housing 32, which may be termed a power input for the transmission, there is provided a torque transmitting or lay shaft, indicated generally at 34, which is connected through the `universal joint 35 to the gear 33 and which has a splined extension 36 connected through a second universal joint 31 to the clutch shaft of a clutch 38,which maybe of the overrunning type described in the copending application of Donald D. Ormsby, Serial No. 256,947, filed February 17; 1939. It will therefore be apparent that whenever the transmission 25 ls in operation there will be' a certain speed relation between the countershaftv 28v and the lay shaft 34 regardless of the directionV of transmission of torque therebetween. The lay shaft 34 is'preferably made with the sliding joint therein to accommodate variations in movement between the main power plant assembly and the supplementary or booster power plant assembly, which is indicated generally at 43, This booster power plant assembly includes an engine 42, which may be any standard type of internal combustion engineV orV Diesel engine and which is supported from the side rail I8' and the cross member I9 by means of suitable brackets 43, 44 and 45, riveted or otherwise lsecured to' these frame members.

Preferably, the motor is hung from the brackets 44 Vand 45, as shown inorevclearly in Figure 1, and is cushioned relative thereto by suitable rubber biscuits 46, or like cushioning means which resiliently support the motor in position but'allow` rear portion of agrega? it to noat in cushioned relationship to the frame. Similarly, rubber biscuits 41 are provided between the engine 42 and the bracket 43 to support the forward end of the engine, it being noted that the engine 42 is mounted in a direction ollposite .to the engine 22 so that the output ends ofthe engines extend toward each other with the engine G2 being laterally olset with respect to the engine 2,2 at one side of the propeller shaft l1. Preferably, the crankshaft of the engine 42 is provided at its forward end with a pulley .or similar driving means for driving a generator 48 supported at the side of the engine assembly, and Vilvliich may also. include a Water pump 0r similar means for circulating cooling fluid from the engine 42 through ka suitable radiator (not shown). The output end of the crankshaft of the engine 42 .extends into the flywheel housing 4,9, and that the engine 42 may be clutched to the shaft 34.

From the description ofthe structure up to this point yit will be apparent that the engine 42 can serve as a supplemental or booster engine for the power plant of the vehicle, since when .the engine 42 is in operation it will drive the shaft 34 and thereby impart torque through the gears 33 and 3b to the countershaft 28 of .the transmission 25. This torque will be supplemental to the torque of the main power plant 22, and consequently .will increase the torque output from the transmission tothe propeller shaft Il, thus supplying the additional torque from the booster engine 42 to the driving axle L4. .Thus the present system includes means for developing additional torque and transmitting the same to the drive train of the vehicle for supplementing the normal torque supplied by the primary engine to increase'the torque transmitted to the driving axle for giving the vehicle either more speed or more power .Whenever the engine .42 is in operation.

While it is apparent the control of the engine 42 might be manual with an additional starting system and controls for this engine .provided for the operator of .the vehicle, so that at any time when he desired additional torque either for climbing grades or for producing a predetermined speed of the vehicle he could start the engine l2 and bring it up .to a speed so that it Would impart torque through the shaft 34 to the transmission, I contemplate providing an automatically operating control system for starting .the engine 42 .and ,delivering its torque to the vehicle under certain predetermined conditions.

Considering now in ,further detail the manner in which the booster engine may be automatically controlled to impart .its driving torque to the vehicle, I have provided in Figure 3 an optional control system that can be employed for this purpose. The primary reason for requiring .the automatic control is .to eliminate the human element which would be present if this control were subject to the operator of the vehicle, and to make surethat ythe supplemental .torque will .be employed only under the conditions for which it is required. For'v example, it is contemplated that this supplementary booster unit be employed in order to maintain the vehicle above a predetermined minimum Speed when climbing grades of a certain percentage slope. Inasmuch as the Aconditions under which rthe booster torque will be vrequired may vary in different localities or in different legislative districts, it is ressential tha-t vthe control system 4be sufficiently 'exible -to allow is there connected to the clutch 33 so' automatic control oi the ralliement @nel 1 sie yarying requirements.

v.In the control .system ,figure 3 the manifold 5U of the main. or prim ry e Aille 32. has a suction connection 5.2 theretp tullio h lil-31?: minates in a vacuum cQhtrQllgd rely@ 53 allrllil toi be mounted on the noyer takevoi housing 32.- Tjhe valve 53 may be arranged se that it will be opened on the occurrence of rclatiyely leu Vagiium in the manifold 50, such as cllrs when ill? throttle of the primary engine 22 is wide geen It is Vdesirable that the valve 55 be opened only when the vehicle speed is within a prede rf mined range Where the `additional power kfrom the engine 4 2 is required. Therefore the YJ? 53 is` conditiorled or released for operation or opening by means of control mechanism, :5.5, such as a latch, which is preferably electrically actuated and has one side of its operating mcizllf Aanism connected through the conductor 45,5 and the relay 5B to the generator 5l of the prhnary engine 2,2. The opposite terminal of control mechanism 5,4 is connected through conductor 5B and control relay 579 to the conductor 611. leading to the ignition system indicated generally ,at e2 for the supplemental or booster .engine 42.

Preferably the relay .5.6 is so designed that it will not .close the circuit between .the generator 51 and the cohduutor 5.5. vuntil the speed o f the vehicle, that is, the speed of engine 22, is above a predetermined minimum. ,'Ihsis to safe-guard the drive axle of the vehicle so .that the booster engine will not operate at very loyv speeds of the vehicle such as starting away from Aa stop or the like Where the, application of too much torque through the very low gear ratios .would impose too great a strain on the driving axle. .In one preferred `.System of control the relay .5,5 may be set so that it does ,not operate until the vehicle speed is above I0 miles per hour.` The operation 0i this relay merely conditions the control mechanlsnl 5 4 for operation, but obviously will not allow .this mechanism to operate until such time as the Circuit is completed through the ycontrol relay -59 which is employed for energizing the ignition circuit of the secondary or supplemental power unit The control relay `5l.) is preierably set so that it Will out in at engine vSpeeds below. 35. miles an hour and will stay in energized position until a, minimum engine speed of y.2 0 miles an hour is reached, aSSllmIlg direct driving engagement or high gear operation. In other Words, during this speed range the relay 59 will be closed to elect the energization of the ignition circuit of the engine ,42. However, this in itself will not operate the engine 42 without some means for starting the engine. This is provided by means of the vacuum controlled clutch operating mechanism .63 which is connected through the conduit r64th the valve '53. The mechanism :63 includes a cylinder having a plunger therein provided with the extending arm |55,` the plunger being normally biased by means of a suitable spring or the like to extended position. When the valve 53 is a1- lovved to open under the influence of control mechanism 54, which occurs only when both relays 5B and 59 are energized, it provides for communication between conduits 52 and 64. The valve 53 is arranged, as set forth above, 'so that it will `be opened only under substantially full open throttle conditions, at which time, even though the vacuum in manifold 50 is relatively low, it is su'lcient so that the mechanism 'B3 will' be actuated to retract arm B5 thereby factu- :mains within the engine.

ating the clutch engaging arm 66 to engage the clutch 38 between lay shaft 34 and engine 42. Inasmuch as lay shaft 34 is being driven from the countershaft of the transmission this results in cranking the motor 42, and since the ignition circuit 62 is also energized, the engine 42 starts and is automatically brought up to full speed by reason of the connection B1 from the arm 55 to the throttle valve in the carburetor 58 connected to the intake manifold 69 of the engine 42. As the engine 42 thus comes up to full speed it overcomes the cranking effort of the shaft 34 and starts to deliver torque to this shaft, thereby imparting torque to the countershaft of the transmissionf25 to supplement the normally available torque of the engine 22. This torque is continuously delivered by the engine 42 as long as a full open throttle condition exists at the primary engine 22, and the speed of the vehicle rerange of 35 to 20 miles per hour.

If the speed of the vehicle drops below 20 miles per hour the control relay 59 is de-energized, thereby deenergizing the ignition circuit for the `booster engine 42 and thus stopping the booster Thus the operator, if he still requires :additional torque, must shift into a lower speed ratio and again bring about a condition of full Aopen throttle. Due to the fact that the relay 59 is controlled as a function of engine speed and not propeller shaft speed, in the lower gear ratio the engine speed will increase to a point where :the relay 59 will again be energized, and under full open throttle conditions the booster engine 42 will again deliver its torque to the driving train. However, if the speed of the vehicle gets to a point below the setting of relay 56, the entire 'booster control system is rendered inoperative, as under such conditions the imparting of additional torque to the drive axle would place too severe a strain thereon.

Similarly, if when the booster engine 42 is operating the additional torque supplied thereby is suflicient to increase the speed of the vehicle above 35 miles an hour, the relay 59 will be deenergized, thereby cutting out the booster engine, as above such speeds it is not contemplated in this particular embodiment of the invention that the booster engine be operated.

Another factor controlling the operation of the booster engine is the throttle condition at the primary engine. For example, if for some reason within the speed range of 20 to 35 miles per hour the operator does not have a full or substantially full open throttle due to the fact that he does not Want to drive any faster than this speed, the booster engine'will not be operated due to the fact that the clutch 38 will be released because of the vacuum condition at the mechanism 63. This disengages the booster engine 42 from the shaft 34 so that whether the booster engine operates or not, it cannot deliver torque to the driving train of the vehicle.

It will be obvious that relays 56 and 59 can be of any desired type and may be designed to operate at any required point, and the speed ranges and limits described in connection with the system shown in Figure 3 are to be understood as being exemplary in character and only for the purpose of describing one manner in which the mechanism might be set for operation, it being obvious that the speed range could be widened or narrowed, raised or lowered, or the throttle control range may be increased to, say, anywhere from 60% full throttle up to full throttle position.

One of the features ofthe present invention is the fact that this system does not interfere in any substantial manner with the conventional type of power plant and drive mechanism installed in a vehicle, and consequently can be added to any vehicles now in operation without requiring any appreciable change in construction-requiring only a connection to the side ot the transmission and the installation of the control system which is mostly electric. One chassis change which has to be made on certain types of vehicles is the shifting of the brake equalizing mechanism in order to have this mechanism pass around the booster engine 42. This is shown clearly in Figure 2 in dotted lines in which the brake equalizing cross rod I I5 has the connections for the rear wheels extending within the side rails I8 and supported at the side rails, as indicated at IIS for the connections II1 to the rear wheel brakes of the vehicle. Other than this chassis change and the mounting of the supporting brackets 43, 44 and 45 on the chassis, the installation of such a booster unit in conventional type vehicles is simple and inexpensive, and can be done byany competent garage or service station mechanic.

It is therefore believed apparent that I have provided a novel type of power system which allows the use of additional torque under certain predetermined conditions but eliminates the expense of operating this additional power supply except at such times that its operation is required, and which therefore renders the entire system very economical in use.

I am aware that numerous changes can be made in the location of the various constituent parts of the assembly herein shown and descrribed and that connection of these parts to other parts may be modified or the inter-relation of the driving connections may be changed without departing in any fundamental manner from the broad concepts and principles disclosed herein. It is intended that the drawings and detailed description hereof be considered merely as exemplfying one manner in which the invention may be carried out and should not be construed in any manner as limiting the invention, but limited only as defined by the scope and spirit of the appended claims.

I claim:

1. In combination, a vehicle chassis including longitudinally extending side rails, a main power unit supported centrally between said side rails at one end of the chassis, a transmission in alinement with and connected thereto having a main shaft and a countershaft, a driving axle for said chassis connected to said transmission main shaft, a secondary power unit supported adjacent one side rail intermediate said transmission and axle and facing in the opposite direction to said main power unit, and means including said countershaft operable to connect said secondary power unit to said transmission main shaft for supplementing the torque to said main power unit.

2. .The combination, in a vehicle having a frame'including spaced longitudinal side rails, a primary power unit centrally mounted between said'rails at one end of said frame, a transmission coupled to one end of said engine in longitudinal alinement therewith between said rails and having acountershaft, a secondary power unit mounted on the inner face of one of said rails rearwardly of said transmission,` a forwardly extending lay shaft connected to one end -of said secondary unit, and a laterally projectine g'eating conneetien between me free end of said lay shaft and the' rear end of said transmission couriter'shaft. Y Y l 3. The combination of claim wherein Said tfvvo" power units are mounted to face in opposite directions in said frame. l y

4. In combination, a vehicle 'chassis having transversely spaced side rails connected interindiate their ends by a cross inerriber,` a main power unit comprising an engine and transmission'. mounted centrally between said rails forwardly of said cross member in longitudinal alinement, a countershaft in said transmission, a laterally .projecting gear train at one side of said transmission connected to said counter-U shaft, a second engine mounted rearwardly of said 'cross member adjacent one of said side rails, and a lay shaft connected between said second engine and said gearing.

5. In combination, a primary power unit, a clutch therefor, a drive axle, a propeller shaft and transmission disposed between said aXle and unit with the transmission connected to said clutch to form a longitudinally alined torque transmitting connection therebetween, 'said transmission having a countershaft, a secondary powverrunit mounted parallel to said propeller shaft in laterally offset position 'and having a power shaft extending forwardly toward said primarypower unit, and a lateral geared connectiii'nl between said transmission countershaft' and power shaft', Awlieby the torque of "said secondary unit is applied to said transmission through a shaft other than that through which the torque of the primary unit is applied.

6. The combination of claim further characterized in the provision of a clutch between said secondary unit and said power shaft.

7. The combination of claim 5 wherein said lateral geared connection is so constructed and arranged that said power shaft is rotating whenever torque is transmitted through said transmission from said primary unit.

8. In combination, a chassis comprising spaced longitudinal side rails, a cross member connecting said rails intermediate their ends, an engine centrally mounted between said rails at the forward end of said chassis, a transmission rigidly bolted to said engine in longitudinal. alinement therewith forwardly of said cross member, a propeller shaft connected to the main shaft of said transmission and passing longitudinally between said rails beneath said cross member, a laterally off-set second engine disposed rearwardly of said cross member and having suspension from said cross member and the adjacent side rail, a clutch for said second engine bolted thereto adjacent said cross member, a power shaft connected at one end to said clutch and extending forwardly of said chassis beneath said cross member, the forward end of said shaft terminating adjacent the rear end of said transmission, and a transverse geared connection between the countershaft of said transmission and said forward end of said shaft.

9. In a vehicle chassis having a pair of laterally spaced side rails spaced apart by transverse cross members, a primary power unit mounted at the front end of said chassis intermediate said rails and having a transmission bolted thereto in longitudinal alinement, a propeller shaft leading from the main shaft of said transmission to the rear of said chassis, one of said cross members being disposed rearwardly of said transmission above said propeller shaft, a.. t

supniementai power una moi-inten 'adiant inner face of one side rail rearwardly f said cross member and facing rearwardly relatif/' te said chassis, a clutch housing secured on said supplemental unit adjacent said dross member, a lay shaft extending forwardly parallel to said propeller shaft Vfrom the clutch housing te ad" jacent-, the rearend of said transmission; and laterally extending' lgea-'ring connecting said forward end of said lay shaft te the printer"-Y shaft of said transmission.

lll. Means for connecting a pair pf ldn`gi= tudinally spaced and laterally offset power uff-its" to a common transmission having av main shaft,- a countershaft and gearing therebetween, `coffiprising a clutch shaft leading from one iiiit joir'nalling one end of said main shaft, said clutch shaft having a driving gear drivingl said' countershaft, the other unit having a llay shaft connected thereto and e'iiterldiiig parallel te 'and' overlapping the rear end of said transmission; and transverse gearing connecting the lay shaftanq seid transmission gearing. y

11. In combination, in a vehicle having a frame, a primary power unit adjacent one ena of the frame, a. transmission connected thereto anni having a countershaft, a propellerV shaft driven by said transmission, a secondaryv power unit at one side of said :frame intermediate the eiids thereof, a clutch thereon; a forwardly e-te'd'- ing lay shaft connected to said clutch, and gear#r ing between said transmission oountershaft arid the forward end of said lay shaft.

12. In combination, in a vehicle, a main power unit including an engine and transmission, a propeller shaft connected to said transmission, a secondary power unit laterally and longitudinally offset rearwardly of said main power unit, and means spaced laterally of and paralleling said propeller shaft adapted to connect said secondary power unit to said transmission forwardly of said propeller shaft.

13. In combination, a primary power unit, a clutch therefor, a propeller shaft and transmission disposed with the transmission connected to said clutch to form a longitudinally alined torque-transmitting connection, said transmission having a countershaft, a secondary power unit mounted parallel to said propeller shaft in laterally offset position and having a power shaft extending forwardly toward said primary power unit, and a lateral geared connection between said transmission countershaft and power shaft, whereby the torque of said secondary unit is applied to said transmission through gearing other than that through which the torque of the primary unit is applied.

14. In combination, in a vehicle having a frame including spaced longitudinally side rails, a primary power unit centrally mounted between said rails at one end of said frame, a transmisison coupled to one end of said engine in longitudinal alinement therewith between said rails and having a shaft, a propeller shaft extending longitudinally rearwardly from said transmission, a secondary power unit mounted between the inner face of one of said rails and said propeller shaft rearwardly of said transmission, a forwardly extending lay shaft connected to one end of said secondary unit, and a laterally projecting gear between the free end of said lay shaft and the rear end of said transmission.

15. In combination, a main power-unit having a transmission including a countershaft, a power input gear on said countershaft, a supplemental power unit, a shaft and gearing extending from said supplemental unit and engaging said power input gear, and a clutch at said supplemental unit operable to connect said supplemental unit to said shaft and gearing.

16. In combination, a primary power unit, a secondary power unit laterally offset from said primary power unit and facing in the opposite direction to that of said primary power unit, a transmission connected to said main power unit intermediate said units and having a countershaft,v an output shaft from said secondary power unit extending parallel to said countershaft and laterally overlying the rear end thereof, a gear on each of said shafts, and an idler gear interposed therebetween whereby the torque from said secondary unit is transmitted in the proper direction' to said countershaft through said gears.

17. In combination, a primary power unit, a transmission therefor having a countershaft, a supplemental power unit laterally offset from said first unit, a laterally projecting power input on said transmission including a gear on said countershaft, and a meshing idler gear, a shaft projecting from said second unit into said power input and having a gear driving said idler gear, and clutch means between said shaft and said second unit.

18. The combination of claim 17 wherein said supplemental power unit faces in a direction opposite to that of said primary power unit and is spaced rearwardly thereof.

' 19. Means for connecting a pair of longitudinally spaced and laterally offset power units to a common transmission having a. main shaft, a countershaft and change-speed gearing therebetween rcomprising a clutch shaft leading from one unit and journalling one end of said main shaft, said clutch shaft having a drive gear driving said countershaft, the other unit having a lay shaft connected thereto and extending parallel to and overlapping the rear end of said transmission countershaft, transverse gearing between said lay shaft and countershaft including an idler gear therebetween connecting the lay shaft to said transmission countershaft for rotation in the same direction as said countershaft is driven by said driving gear.

GEORGE D. WILCOX.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Y Date 

